If you check the MD3000/MD3000i support matrix, Red Hat 5.5 isn't supported (2.6.18-194 is the Red Hat 5.5 kernel). This kernel has been out several months without Dell adding it to the support matrix. This probably means that that kernel won't work (properly) with the RDAC driver that's currently available.

I'd suggest you

- revert to a supported kernel and stay on that till Dell comes out with a newer resource CD (in combination with an updated support matrix that shows that RHEL 5.5 is supported) and update the RDAC driver in combination with updating the kernel

Or, if failover/redundancy isn't too important;

- you reboot the server to see if that finds the disk, and accept that if a failure were to occur, you may not have failover

Does anyone know if 5.5 is supported yet?

Ok, I have the following firmware.

07.35.22.61 - is this second gen? Don't see anything actually saying it is, but it would seem so.

Do I need to install an updated driver then to make 5.5 work and can this be done online or should I schedule downtime? 

Ok, I see that this is second gen, so my only question is about the drivers?

RHEL 5.5 appears to be supported with 2nd gen firmware

http://support.dell.com/support/edocs/systems/md3000i/en/

Check out the support matrix above.

You'll want to verify that you have the latest DRAC driver installed (don't try to use linux native multipathing). You can check the latest version on the CD/ISO in the linux\RPMS\rh5 folder (compare the installed version to the version number in the filename).

Installed rdac

linuxrdac-09.03.0C06.0030-1dkms

On cd

linuxrdac-09.03.0C06.0234-1dkms

Should I just do a rpm -Uvh ? then run hot_add?

Also will I need to restart the host?

the simplest method would be to use the RCD and run the install script. This will ensure that all the correct versions and supporting modules are installed.

I do believe that you have to reboot the host after install but I am not sure....wouldn't hurt to do it :-D

Thanks will do.